[Drifter]

The 270K engine currently runs quite well aside from burning coolant. The previous owner says sometimes it stumbles when first starting or when the engine restarts after being in EV-mode (a common symptom among blown head gasket priuses), but I experienced none of that on my test drive & 25-mile drive home. Coolant temps never exceeded 209 on the scangauge, but it was downhill on a very mild day. Its head gasket likely failed due to a severe misfire that went ignored too long. A new coil solved the misfire 8,000 miles ago, but the damage to the head gasket was already done. Blue Devil head gasket sealant was installed which limited the head gasket symptoms for a while, but coolant loss came back.

The 90K mile junkard engine presumably ran when the donor car was rear ended nearly 5 years ago. Standard practice is to drain all fluids once it gets to a salvage yard to be parted out so I don't know that it doesn't leak today when running. Visually it looks like the valve cover gaskets were weeping a bit, but that's almost universal on high mileage 3MZ engines. A little bit of clean-looking SLL coolant sloshed out on the drive home, so it is unlikely the head gaskets were blown.

The 3MZ-FE engine is an interference engine with timing belts due every ~90K so it'll get replaced. The water pump, tensioner, idler are right there and particularly easy to replace while the engine is out of the car. So are the crank and cam seals - along with the valve cover gaskets. Valve lash is supposed to be checked every ~70K, but with solid cam-over-shims this service is usually ignored. I'll check it while I'm in there but would be surprised if any are out of the generous +/- 0.005 tolerance.

The oil pan is a 2-piece design that I think uses form-in-place gasket from the factory. It and the head gaskets I'd planned on leaving alone, but am now debating replacing just due to age.